1. Technical Field
The present invention relates to a pair of shutter glasses and an image display system.
2. Related Art
There has been a known image display system including an image display apparatus, such as a projector, and a pair of shutter glasses, such as a pair of glasses with built-in liquid crystal shutters.
In the image display system, a viewer wears the shutter glasses and views an image projected from the image display apparatus on a screen or any other suitable surface for stereoscopic image recognition.
The shutter glasses typically includes a pair of shutter members formed, for example, of liquid crystal shutters and a frame member in which the pair of shutter members and a drive circuit, a drive power supply, and other components that drive the pair of shutter members are accommodated.
The thus configured shutter glasses, which include a large number of components, tend to be heavier than a pair of typical glasses for diopter correction and hence tend to cause fatigue when worn for a long period.
To address the problem, a technique for allowing a user to wear a pair of shutter glasses more comfortably has been proposed (see JP-A-9-5904, for example).
In the shutter glasses (liquid crystal shutter glasses) described in JP-A-9-5904, a battery and electric parts for driving the shutter glasses are so accommodated in right and left side light blocking portions, which form a first eyeglass frame, that the left and right portions of the shutter glasses are balanced in terms of weight, whereby fatigue of the user who wears the shutter glasses is reduced.
However, the shutter glasses described in JP-A-9-5904, in which the battery and the electric parts are accommodated in the vicinity of the shutter members (liquid crystal shutters) disposed on the front side of the shutter glasses, disadvantageously have their center of gravity shifted frontward. As a result, when the viewer wears the shutter glasses, a large part of the weight of the shutter glasses acts on the viewer's nose, which supports the front portion of the shutter glasses. In this case, the viewer feels the shutter glasses to be heavier than they actually are, disadvantageously resulting in uncomfortable wearing experience and fatigue when the viewer views an image.